Bioinformatics and Functional Genomics 3rd Edition

Chapter 20: The Human Genome

In 1953 Francis Crick and James Watson described the double-helical nature of DNA. By 2003, 50 years later, the human genome sequence was essentially completed. In the following decade the introduction of next-generation sequencing has allowed tens of thousands of genomes (and perhaps hundreds of thousands of exomes) to be sequenced. We can ask two fundamentally different questions:

What makes us different than other creatures? We can compare the human and chicken genomes, focusing on the few regions that are perfectly conserved (see Chapter 8 where we do this as an exercise).

What makes us different than each other? We can sequence the genomes of people from diverse geographic regions, focusing on the few regions that are different among humans (such as single nucleotide polymorphisms).

In this chapter we explore the human genome in terms of its basic features. We follow the outline of two key 2001 papers on the completion of the human genome, one from the HumAsan Genome Project (a public, multinational consortium) and one from Celera Genomics. We survey the chromosomes (1-22, X, Y, and the mitochondrial genome) and we discuss major initiatives such as HapMap and the 1000 Genomes Project.

Publications reporting the sequence of the human genomes and chromosomes

To find accession numbers of chromosomes from 100 to 200 Mb, use the Entrez Nucleotide command txid9606[Organism:exp] 100000000:200000000[slen]. To see a list of chromosomal accession numbers, visit this NCBI site.